Control device

ABSTRACT

A control device of an automatic drive vehicle includes: an information acquisition unit that acquires power generator information as information on a power generator provided in the automatic drive vehicle; an operation control unit that switches between a first state in which automatic driving of the automatic drive vehicle is executed without restriction and a second state in which the automatic driving is partially or entirely restricted; and a determination unit that determines whether to perform switching to the second state by the operation control unit.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation Application of U.S. patentapplication Ser. No. 16/422,066 filed May 24, 2019, which is a BypassApplication of International Application No. PCT/JP2017/039321 filedOct. 31, 2017 which designated the U.S. and claims priority to JapanesePatent Application No. 2016-242028 filed on Dec. 14, 2016, the contentsof which are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates to a control device of an automatic drivevehicle.

BACKGROUND

Automatic drive vehicles have been developed. Automatic drive vehiclescan automatically perform some or all of driving operations that hadbeen performed by a driver of the vehicle or can assist the driver inperforming the driving operations. Some of these automatic drivevehicles automatically perform all the operations such as steeringduring running of the vehicle, others automatically perform onlytemporary driving operations at the time of a lane change, for example.

SUMMARY

A control device according to the present disclosure is a control deviceof an automatic drive vehicle. The control device includes: aninformation acquisition unit that acquires power generator informationas information on a power generator provided in the automatic drivevehicle; an operation control unit that switches between a first statein which automatic driving of the automatic drive vehicle is executedwithout restriction and a second state in which the automatic driving ispartially or entirely restricted; and a determination unit thatdetermines based on the power generator information whether to performswitching to the second state by the operation control unit.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a diagram schematically illustrating a configuration of acontrol device according to a first embodiment;

FIG. 2 is a diagram schematically illustrating a configuration of analternator installed in an automatic drive vehicle;

FIG. 3 is a flowchart of a process performed by the control deviceillustrated in FIG. 1 ;

FIG. 4 is a flowchart of a process performed by the control deviceillustrated in FIG. 1 ;

FIG. 5 is a modification example of the flowchart illustrated in FIG. 4;

FIG. 6 is another modification example of the flowchart illustrated inFIG. 4 ;

FIG. 7 is a flowchart of a process performed by a control deviceaccording to a second embodiment; and

FIG. 8 is a flowchart of a process performed by a control deviceaccording to a third embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Like conventional vehicles with no automatic driving function, anautomatic drive vehicle is equipped with a storage battery for storingpower and supplying the same to auxiliary devices. The automatic drivevehicle is also equipped with a power generator for supplying power tothe storage battery. The power generator is intended to generate powerby driving force of the internal combustion engine and supply thegenerated power to the storage battery and the auxiliary devices.

In the event of an abnormality in the power generator, no power issupplied from the power generator to the storage battery, and thus thepower stored in the storage battery gradually decreases. Accordingly,with a lapse of time, enough power is not supplied from the storagebattery to the auxiliary devices, so that the auxiliary devices may notbe able to perform normal operation.

In particular, an automatic drive vehicle includes a large number ofauxiliary devices that consume power such as an electrical brakingdevice, for example. Therefore, in the event of a lack of power due toan abnormality in the power generator, the automatic drive vehiclecannot start normally or continue automatic driving, and thus theoperations of the automatic drive vehicle may become unstable. Forexample, an in-vehicle camera may become unable to operate normally dueto a lack of power and may not correctly recognize obstacles around thevehicle.

An embodiment provides a control device of an automatic drive vehiclethat prevents the automatic drive vehicle from becoming unstable inoperations due to an abnormality in a power generator.

A control device according to the present disclosure is a control deviceof an automatic drive vehicle. The control device includes: aninformation acquisition unit that acquires power generator informationas information on a power generator provided in the automatic drivevehicle; an operation control unit that switches between a first statein which automatic driving of the automatic drive vehicle is executedwithout restriction and a second state in which the automatic driving ispartially or entirely restricted; and a determination unit thatdetermines based on the power generator information whether to performswitching to the second state by the operation control unit.

In the control device, the determination unit determines based on thepower generator information as the information relating to the powergenerator whether to perform switching to the second state by theoperation control unit, that is, whether the automatic driving ispartially or entirely restricted. Accordingly, when it is determinedthat the power generator has failed, for example, automatic driving ispartially restricted to continue the automatic driving within the rangeof consumable power.

According to the present disclosure, it is possible to provide a controldevice of an automatic drive vehicle that prevents the automatic drivevehicle from becoming unstable in operations due to an abnormality inthe power generator.

Hereinafter, embodiments will be described with reference to theattached drawings. For easy understanding of the descriptions, identicalcomponents illustrated in the drawings are given identical referencesigns as much as possible and redundant descriptions thereof will beomitted.

A control device 100 according to a first embodiment is installed in anautomatic drive vehicle 200 (not entirely illustrated) to control theautomatic drive vehicle 200. Prior to the description of the controldevice 100, a configuration of the automatic drive vehicle 200 will bedescribed with reference to FIG. 1 .

The automatic drive vehicle 200 in the present embodiment is structuredas a vehicle that can automatically run without depending on thedriver's operations. The automatic drive vehicle 200 can switch betweena state in which the automatic driving as described above is performedand a state in which conventional running is performed based on thedriver's operations (that is, no automatic driving is performed). Theautomatic drive vehicle 200 includes an internal combustion engine 210,a starter 220, a power generator 300, a battery 240, and a vehicle ECU201.

The internal combustion engine 210 is a vehicle engine. The internalcombustion engine 210 burns a supplied fuel therein to generate drivingforce necessary for running of the automatic drive vehicle 200.

The starter 220 is a rotary electrical machine that operates with asupply of power from the battery 240 described later. The starter 220rotates a crankshaft (not illustrated) of the internal combustion engine210 to perform cranking, thereby starting the internal combustion engine210. The starter 220 is equivalent to one of auxiliary devices necessaryfor running of the automatic drive vehicle 200.

The power generator 300 is a power generator driven by the internalcombustion engine 210. When the internal combustion engine 210 isoperating, the power generator 300 generates power and supplies thepower to the components of the automatic drive vehicle 200. A specificconfiguration of the power generator 300 will be described later.

As illustrated in FIG. 1 , in a path to which the power is output fromthe power generator 300, a shutoff device 230 is provided to switchopening and closing of the path. The shutoff device 230 is formed as arelay and its opening and closing operations are controlled by thecontrol device 100. When the shutoff device 230 is in the closed state,the power generated by the power generator 300 is supplied to theauxiliary devices such as the battery 240 and an electrical powersteering device 250. When the shutoff device 230 is in the open state,the power generated by the power generator 300 is not supplied to thebattery 240 or any of the auxiliary devices.

The battery 240 is a storage battery to supply power to the starter 220and other devices. The power output (discharged) from the battery 240 issupplied together with the power output from the power generator 300 tothe components of the automatic drive vehicle 200. In particular, whenthe internal combustion engine 210 is started by the starter 220, thepower generator 300 is stopped and thus the starter 220 is supplied withpower from the battery 240 alone. As described above, the battery 240 isprovided as a device for supplying the starter 220 with the powernecessary for starting of the internal combustion engine 210. Thebattery 240 also supplies the power necessary for operations of thecontrol device 100.

The battery 240 can store the power generated by the power generator 300(that is, charging). The input and output of power to and from thebattery 240 are performed via a power convertor not illustrated. Thepower convertor is operated via the control device 100. Instead of sucha mode, a separate ECU may be provided to control the battery 240 andthe power convertor. In this case, the control device 100 controlscharging and discharging of the battery 240 through communications withthe ECU.

The vehicle ECU 201 is a higher-level control device that is provided tocontrol the overall operations of the automatic drive vehicle 200. Theprocesses performed by the vehicle ECU 201 include a process ofdetermining whether to shift the automatic drive vehicle 200 to a statein which the operation of the internal combustion engine 210 is stopped,that is, an idle stop state. In addition, the processes performed by thevehicle ECU 201 include a process of determining whether toautomatically return the automatic drive vehicle 200 from the idle stopstate (that is, whether to restart the internal combustion engine 210).Some of the processes performed by the control device 100 are performedbased on control signals transmitted from the vehicle ECU 201.

The automatic drive vehicle 200 is equipped with a plurality ofpower-consuming devices that operates with a supply of power from thebattery 240 or the power generator 300. Among the plurality ofpower-consuming devices, FIG. 1 illustrates the electrical powersteering device 250, an electric braking device 260, an in-vehiclecamera 270, and a navigation system 280.

The electrical power steering device 250 is a device that appliessteering force resulting from electric power to a steering shaft. Whenthe automatic drive vehicle 200 is performing automatic driving, theelectrical power steering device 250 generates all the steering forcenecessary for running along the lane without depending on the driver'ssteering operations. When the automatic drive vehicle 200 is notperforming automatic driving, the electrical power steering device 250applies auxiliary steering force to the steering shaft to reduce thedriver's force to be applied to the steering wheel. The electrical powersteering device 250 is equivalent to one of the auxiliary devicesnecessary for running the automatic drive vehicle 200.

Operations of the electrical power steering device 250 are controlled bythe control device 100 described later. In another mode, a separate ECUmay be provided to control the electrical power steering device 250. Inthis case, the control device 100 controls the operations of theelectrical power steering device 250 through communications with theECU.

The electric braking device 260 is a device that generates braking forceresulting from power to decelerate or stop the automatic drive vehicle200. The electric braking device 260 is equivalent to one of theauxiliary devices necessary for running the automatic drive vehicle 200.

When the automatic drive vehicle 200 is performing automatic driving,the electric braking device 260 automatically generates braking forcewithout depending on the driver's braking operations. The operations ofthe electric braking device 260 are controlled by the control device100. In another mode, a separate ECU may be provided to control theelectric braking device 260. In this case, the control device 100controls the operations of the electric braking device 260 throughcommunications with the ECU.

The in-vehicle camera 270 is a camera that captures images of thesurroundings of the automatic drive vehicle 200, in particular, imagesof the area in front of the automatic drive vehicle 200. The in-vehiclecamera 270 has a CMOS sensor, for example. The in-vehicle camera 270transmits data of the captured images to the control device 100. Thecontrol device 100 analyzes the images to detect the positions ofobstacles around the automatic drive vehicle 200 and the lane on theautomatic drive vehicle 200 is running. This makes it possible toautomatically perform steering and braking for avoiding a collision withan obstacle and steering for running along the lane. The imageprocessing as described above may be performed by an ECU providedseparately from the control device 100.

In addition to the in-vehicle camera 270, a radar device and a laserdevice may be provided to detect obstacles.

The navigation system 280 is a system that identifies the currentrunning location of the automatic drive vehicle 200 by GPS. Thenavigation system 280 can generate a route on which the automatic drivevehicle 200 is to run to arrive at the destination, display the route tothe passenger, and guide the automatic drive vehicle 200 to run alongthe route.

Other components of the automatic drive vehicle 200 will be described.An automatic driving switch 290 is provided at the driver's seat of theautomatic drive vehicle 200. The automatic driving switch 290 is aswitch to be operated by the driver to switch between on and off statesof automatic driving. When the automatic driving switch 290 is turnedon, the automatic drive vehicle 200 performs automatic driving. When theautomatic driving switch 290 is turned off, the automatic drive vehicle200 does not perform automatic driving. That is, the automatic drivevehicle 200 runs based on the driver's manual driving operations.

The automatic drive vehicle 200 is provided with a large number ofsensors to measure the physical amounts of the components. Among theplurality of sensors, FIG. 1 illustrates a current sensor 241, a voltagesensor 242, and a temperature sensor 243.

The current sensor 241 is a sensor to measure the value of a currentinput and output to and from the battery 240. The current measured bythe current sensor 241 is transmitted as an electrical signal to thecontrol device 100.

The voltage sensor 242 is a sensor to measure an inter-terminal voltageof the battery 240. The inter-terminal voltage measured by the voltagesensor 242 is transmitted as an electrical signal to the control device100.

The temperature sensor 243 is a sensor to measure the temperature of thebattery 240. The temperature of the battery 240 measured by thetemperature sensor 243 is transmitted as an electrical signal to thecontrol device 100.

Instead of the mode as described above, the measurement values of thecurrent sensor 241 and others may be transmitted to the control device100 via another ECU to control the battery 240 and the power convertor.

A configuration of the power generator 300 will be described withreference to FIG. 2 . The power generator 300 is formed as an alternatorthat has a stator 310, a rotor 320, and a regulator 360.

The stator 310 is a member that is fixed in the housing of the powergenerator 300. The stator 310 is provided with a stator coil 311. Therotor 320 is a member that is rotatably held in the housing. The rotor320 is provided with a rotor coil 321.

A portion of the rotor 320 on one side (the left side in FIG. 2 ) alongits rotation axis constitutes a columnar shaft 330 that protrudesoutward. The shaft 330 is rotatably held by a bearing not illustrated. Atip of the shaft 330 is provided with a pulley 340. When the internalcombustion engine 210 is driven, the driving force of the internalcombustion engine 210 is transmitted to the pulley 340 via a belt notillustrated. Accordingly, the rotor 320 rotates around its central axis.

A portion of the rotor 320 on the other side (the right side in FIG. 2 )along its rotation axis constitutes a columnar shaft 350 and protrudesoutward. The shaft 350 is rotatably held by a bearing not illustrated.The shaft 350 is provided with a pair of slip rings 351 and 352 thataccepts power to be supplied to the rotor coil 321. The slip ring 351 isconductive to one of lead lines that leads to the rotor coil 321, andthe slip ring 352 is conductive to the other of the lead lines thatleads to the rotor coil 321.

The regulator 360 adjusts the magnitude of a current to flow to therotor coil 321, thereby adjusting the magnitude of power to be generatedby the power generator 300. The regulator 360 is supplied with powerfrom the battery 240 via a lead line 380. After adjusting the magnitudeof the power, the regulator 360 outputs the power to lead lines 370. Thepair of lead lines 370 has brushes 361 and 362 at their tips. The brush361 is in contact with the surface of the slip ring 351, and the brush362 is in contact with the surface of the slip ring 352. Accordingly,even when the shaft 350 rotates together with the rotor 320, theregulator 360 can supply power to the rotor coil 321.

The regulator 360 has a current sensor 363 and a voltage sensor 364therein. The current sensor 363 is a sensor that measures the value of acurrent output from the regulator 360 to the lead lines 370, that is,the value of a current supplied to the rotor coil 321. The value of thecurrent measured by the current sensor 363 is transmitted as anelectrical signal to the control device 100. The voltage sensor 364 is asensor that measures the value of a voltage output from the regulator360 to the lead lines 370, that is, the value of a voltage applied tothe rotor coil 321. The value of the voltage measured by the voltagesensor 364 is transmitted as an electrical signal to the control device100.

When the power from the regulator 360 is supplied to the rotor coil 321,the rotor coil 321 is excited. When the rotor 320 rotates in this state,an inductive current is generated in the stator coil 311. The inductivecurrent is taken out to the outside via lead lines 390 and is suppliedto the battery 240 and others as described above.

The magnitude of the current supplied from the regulator 360 to therotor coil 321 is adjusted by a power control unit (PCU) 202 provided inthe automatic drive vehicle 200. The PCU 202 controls the operations ofthe regulator 360 by transmitting control signals to the regulator 360,thereby to adjust the current to be supplied from the regulator 360 tothe rotor coil 321. The PCU 202 monitors the magnitude of a systemvoltage in the automatic drive vehicle 200 and adjusts the current to besupplied to the rotor coil 321 based on the monitored magnitude, therebyto control the amount of power generated by the power generator 300. Inanother aspect, the control device 100 may play the role of the PCU 202as described above.

The lead line 380 is provided with a current sensor 381 and a voltagesensor 382. The current sensor 381 is a sensor that measures the valueof a current supplied from the battery 240 to the regulator 360. Thevalue of the current measured by the current sensor 381 is transmittedas an electrical signal to the control device 100. The voltage sensor382 is a sensor that measures the value of a voltage applied from thebattery 240 to the regulator 360. The value of the voltage measured bythe voltage sensor 382 is transmitted as an electrical signal to thecontrol device 100.

The lead lines 390 are provided with a current sensor 391 and a voltagesensor 392. The current sensor 391 is a sensor that measures the valueof a current output from the power generator 300 to the outside, thatis, the value of a current generated in the stator coil 311. The valueof the current measured by the current sensor 391 is transmitted as anelectrical signal to the control device 100 and the regulator 360. Thevoltage sensor 392 is a sensor that measures the value of a voltageoutput from the power generator 300 to the outside, that is, the valueof a voltage generated in the stator coil 311. The value of the voltagemeasured by the voltage sensor 392 is transmitted as an electricalsignal to the control device 100 and the regulator 360.

The regulator 360 adjusts the magnitude of the current to be supplied tothe rotor coil 321 such that the value of the voltage measured by thevoltage sensor 392 meets a predetermined target value. Accordingly, evenwhen the number of rotations of the rotor 320 varies, the magnitude ofthe voltage output from the power generator 300 can be kept constant.

A configuration of the control device 100 will be described withreference again to FIG. 1 . The control device 100 is configured as acomputer system having a CPU, a ROM, and a RAM. The control device 100includes, as functional control blocks, an information acquisition unit110, an internal combustion engine control unit 120, an operationcontrol unit 130, a shutoff control unit 140, a storage unit 150, acommunication unit 160, and a determination unit 170.

The thus configured control device 100 may be a single computer systemor a plurality of computer systems that operate in conjunction with oneanother to function as the control device 100 on the whole. Part of allof the control device 100 may be installed separately from the automaticdrive vehicle 200 to control the automatic drive vehicle 200 throughcommunications with the automatic drive vehicle 200.

The information acquisition unit 110 acquires power generatorinformation as information relating to the power generator 300. Thepower generator information includes the length of a period of time fromthe installation of the power generator 300 in the automatic drivevehicle 200 to the present time, that is, the duration of use of thepower generator 300. The power generator information also includescurrent values and voltage values measured by the current sensor 381,the voltage sensor 382, the current sensor 363, the voltage sensor 364,the current sensor 391, and the voltage sensor 392.

The power generator information further includes the temperature of thebattery 240 measured by the temperature sensor 243. The reason why thetemperature of the battery 240 is used as part of the power generatorinformation is that, with an increase in the amount of power generatedby the power generator 300, the value of the current supplied to thebattery 240 becomes larger and the temperature of the battery 240increases accordingly.

The internal combustion engine control unit 120 controls the operationsof the internal combustion engine 210 to shift to the idle stop state inwhich the internal combustion engine 210 is stopped and to return fromthe idle stop state (that is, the restarting of the internal combustionengine 210). The internal combustion engine control unit 120 can stopsupply of a fuel to the internal combustion engine 210 to stop theinternal combustion engine 210 and shift to the idle stop state. Theinternal combustion engine control unit 120 can also operate the starter220 to start the internal combustion engine 210 and return from the idlestop state. The internal combustion engine control unit 120 obtains thepresent operating state of the internal combustion engine 210 bydetecting the number of rotations of the crankshaft by a sensor (notillustrated), for example.

The processes by the internal combustion engine control unit 120described above are performed by the internal combustion engine controlunit 120 controlling directly the operations of the starter 220 andothers. In another mode, the foregoing processes may be performed byanother ECU to control the starter 220 and the internal combustionengine 210 communicating with the internal combustion engine controlunit 120.

The internal combustion engine control unit 120 brings the internalcombustion engine 210 into a temporarily stopped state (idle stop state)while the automatic drive vehicle 200 is waiting for a traffic light,for example. In addition, the internal combustion engine control unit120 brings the internal combustion engine 210 into a temporarily stoppedstate while the automatic drive vehicle 200 is freewheeling such asrunning on a flat road, for example. This suppresses wastefulconsumption of a fuel and emission of an exhaust gas.

The internal combustion engine control unit 120 restarts the internalcombustion engine 210 when the driving force of the internal combustionengine 210 becomes necessary for running or when the power generation bythe power generator 300 becomes necessary for air-conditioning. Theswitching of operating state of the internal combustion engine 210 asdescribed above is automatically performed by the internal combustionengine control unit 120 without depending on the driver's operations.

In the present embodiment, the determinations on whether to shift to theidle stop state and whether to return from the idle stop state are madeby the vehicle ECU 201, not by the internal combustion engine controlunit 120. The vehicle ECU 201 transmits a control signal to the internalcombustion engine control unit 120, thereby to cause the internalcombustion engine control unit 120 to shift to the idle stop state.

When the driving force for running becomes necessary in the idle stopstate, the vehicle ECU 201 transmits a control signal for generating thedriving force necessary for running of the automatic drive vehicle 200(hereinafter, also called “first request”) to the internal combustionengine control unit 120. When the power generation by the powergenerator 300 becomes necessary in the idle stop state, the vehicle ECU201 transmits a control signal for causing the power generator 300 tostart power generation (hereinafter, also called “second request”) tothe internal combustion engine control unit 120. The internal combustionengine control unit 120 is configured to, upon receipt of at leasteither of the first request and the second request, start the internalcombustion engine 210 to return from the idle stop state.

The operation control unit 130 performs a process of switching between astate in which the automatic drive vehicle 200 executes automaticdriving and a state in which the automatic drive vehicle 200 executes noautomatic driving. The operation control unit 130 performs the processbased on an operation by the driver on the automatic driving switch 290.

The automatic driving in the present embodiment includes a control ofautomatically steering the automatic drive vehicle 200 (hereinafter,also called “automatic steering”), a control of automatically brakingthe automatic drive vehicle 200 (hereinafter, also called “automaticbraking”), and a control of automatically adjusting driving force of theautomatic drive vehicle 200 (hereinafter, also called “automaticdriving”).

During automatic driving, the automatic drive vehicle 200 can take afirst state in which the foregoing three controls are executed withoutrestriction or a second state in which at least one of the foregoingthree controls is restricted. The second state includes a state in whichonly one or two of automatic steering, automatic driving, and automaticdriving are executed and the other(s) is not executed (that is,automatic driving is partially restricted). The second state alsoincludes a state in which none of automatic steering, automatic driving,and automatic driving is executed (that is, the automatic driving isentirely restricted).

The “restricted” state described above includes a state in which noautomatic driving and others are executed and a state in which automaticdriving and others are executed under constraints. The “executed stateunder constraints” refers to, for example, a state in which automaticdriving is executed only within a range of running speeds not exceeding50 km/h.

The operation control unit 130 performs not only the process ofswitching between the state in which the automatic drive vehicle 200executes automatic driving and the state in which the automatic drivevehicle 200 executes no automatic driving but also a process ofswitching between the first state and the second state. The operationcontrol unit 130 switches the state of the automatic drive vehicle 200but does not determine to which of the states the automatic drivevehicle 200 is to be switched. This determination is made by thedetermination unit 170 described later.

The shutoff control unit 140 controls the operations of the shutoffdevice 230. The shutoff control unit 140 controls the operations of theshutoff device 230 based on the determination made by the determinationunit 170 (described later) to switch between opening and closing of thepath to which power from the power generator 300 is output.

The storage unit 150 is a non-volatile memory that is provided in thecontrol device 100. The type of information stored in the storage unit150 will be described later.

The communication unit 160 is an interface for the control device 100 tocommunicate with the outside. The communications between the controldevice 100 and the vehicle ECU 201 are performed via the communicationunit 160.

An external device 400 illustrated in FIG. 1 is connected to theautomatic drive vehicle 200 when the automatic drive vehicle 200 issubjected to inspection or maintenance (for example, replacements of thebattery 240 and the power generator 300). The external device 400communicates with the automatic drive vehicle 200 via the communicationunit 160 to acquire the states of the components of the automatic drivevehicle 200 and display the same on a screen or rewrite part of theinformation stored in the storage unit 150 of the automatic drivevehicle 200. The external device 400 is not connected to the automaticdrive vehicle 200 in the running state but is illustrated in FIG. 1 forthe convenience of description.

The determination unit 170 decides whether to start (or continue)automatic driving or determines in which of the first and second statesto execute automatic driving. In particular, the determination unit 170is configured to determine whether to perform switching to the secondstate by the operation control unit 130 based on the power generatorinformation acquired by the information acquisition unit 110. Theoperation control unit 130 switches the state of the automatic drivevehicle 200 according to the determination made by the determinationunit 170. The determination made by the determination unit 170 will bespecifically described later.

A specific flow of a process executed by the control device 100 will bedescribed with reference to FIG. 3 . The series of steps illustrated inFIG. 3 are repeatedly executed by the control device 100. This processis performed both in the state in which the automatic drive vehicle 200executes automatic driving and the state in which the automatic drivevehicle 200 executes no automatic driving.

In the first step S01, the information acquisition unit 110 acquires thepower generator information. As the power generator information, theinformation acquisition unit 110 acquires the current values and thevoltage values measured by the current sensor 381, the voltage sensor382, the current sensor 363, the voltage sensor 364, the current sensor391, the voltage sensor 392.

The storage unit 150 stores the date and time when the power generator300 was installed in the automatic drive vehicle 200. The informationacquisition unit 110 calculates the duration of use of the powergenerator 300 based on the date and time. In step S01, the informationacquisition unit 110 also acquires the calculated duration of use of thepower generator 300 as the power generator information. The date andtime is written to the storage unit 150 by the external device 400connected at the time of replacement of the power generator 300.

After step S01, it is determined in step S02 whether an abnormality hasoccurred in the power generator 300. The determination is made by thedetermination unit 170. The abnormality determined here includes a statein which power generation is not sufficiently performed by the powergenerator 300 (hereinafter, also called “underpower generation state”).The abnormality in the power generator 300 also includes a state inwhich power generation by the power generator 300 is excessive(hereinafter, also called “overpower generation state”).

A method for determining whether the power generator 300 is in theunderpower generation state will be described. In step S02, when thecurrent value measured by the current sensor 391 (that is, the currentvalue in the stator coil 311) is equal to or less than a predeterminedvalue, it is determined that the power generator 300 is in theunderpower generation state. In addition, when the voltage valuemeasured by the voltage sensor 392 (that is, the voltage value in thestator coil 311) is equal to or less than a predetermined value, it isalso determined that the power generator 300 is in the underpowergeneration state.

In step S02, when the current value measured by the current sensor 363(that is, the current value in the rotor coil 321) is equal to or lessthan a predetermined value, it is determined that the power generator300 is in the underpower generation state resulting from abrasion of thebrushes 361 and 362. In addition, when the voltage value measured by thevoltage sensor 364 (that is, the voltage value in the rotor coil 321) isequal to or greater than a predetermined value, it is determined thatthe power generator 300 is in the underpower generation state resultingfrom abrasion of the brushes 361 and 362.

Further, in step S02, when the current value measured by the currentsensor 381 is equal to or less than a predetermined value, it isdetermined that the power generator 300 is in the underpower generationstate resulting from a connection failure of the terminal portion. Whenthe voltage value measured by the voltage sensor 382 is equal to orgreater than a predetermined value, it is determined that the powergenerator 300 is in the underpower generation state resulting from aconnection failure of the terminal portion.

The determinations based on the current values and the voltage valuesdescribed above may be made based on their respective absolute values orbased on the amounts of changes in the measured values when changing theinternal combustion engine 210 from the stopped state to the operatingstate. For example, when a value obtained by subtracting the voltagevalue measured by the voltage sensor 392 while the internal combustionengine 210 is stopped from the voltage value measured by the voltagesensor 392 while the internal combustion engine 210 is operating issmaller than a predetermined value, it may be determined that the powergenerator 300 is in the power generation state.

The foregoing determinations on whether the power generator 300 is inthe underpower generation state may be performed on all the plurality ofitems listed above or based on only some of the items.

Among the foregoing determinations, the determination based on thecurrent value, the determination based on the regulator voltage (thevoltage value measured by the voltage sensor 382), and the determinationbased on the rotor voltage (the voltage value measured by the voltagesensor 364) may be performed only at a timing when a system voltage hasbecome lower than a predetermined value or at a timing when the PCU 202has issued a power generation instruction. This is because, when thesystem voltage is high to some degree, the current to be supplied to therotor coil 321 may be reduced to suppress the amount of power generationeven if no abnormality has occurred. The system voltage refers to aninter-terminal voltage of the battery 240, for example.

Among the determinations listed above, the determination based on thestator voltage value (the voltage value measured by the voltage sensor392) may be made only at a timing when the PCU 202 has issued a powergeneration instruction.

A method for determining whether the power generator 300 is in theoverpower generation state will be described. In step S02, when thecurrent value measured by the current sensor 391 (that is, the currentvalue in the stator coil 311) is equal to or greater than apredetermined value, it is determined that the power generator 300 is inthe overpower generation state. In addition, when the voltage valuemeasured by the voltage sensor 392 (that is, the voltage value in thestator coil 311) is equal to or greater than a predetermined value, itis determined that the power generator 300 is in the overpowergeneration state.

In step S02, when the current value measured by the current sensor 363(that is, the current value in the rotor coil 321) is equal to orgreater than a predetermined value, it is determined that the powergenerator 300 is in the overpower generation state resulting from afailure of the regulator 360. In addition, when the voltage valuemeasured by the voltage sensor 364 (that is, the voltage value in therotor coil 321) is equal to or greater than a predetermined value, it isdetermined that the power generator 300 is in the overpower generationstate resulting from a failure of the regulator 360.

Further, in step S02, when the current value measured by the currentsensor 381 is equal to or greater than a predetermined value, it isdetermined that the power generator 300 is in the overpower generationstate resulting from a failure of the regulator 360. In addition, whenthe voltage value measured by the voltage sensor 382 is equal to or lessthan a predetermined value, it is determined that the power generator300 is in the overpower generation state resulting from a failure of theregulator 360.

In step S02, when the temperature of the battery 240 measured by thetemperature sensor 243 exceeds a predetermined value, it is determinedthat the power generator 300 is in the overpower generation state. Thisis because it is estimated that the power supply to the battery 240increases when the temperature of the battery 240 rises.

The foregoing determinations on whether the power generator 300 is inthe overpower generation state may be performed on all the plurality ofitems listed above or based on only some of the items.

At the determination on whether the power generator 300 is in theunderpower generation state or the overpower generation state, theportions measured by the current sensor 391, the voltage sensor 392, andothers may be different from those illustrated in FIG. 2 . For example,instead of the voltage value measured by the voltage sensor 392, thevoltage value measured by the voltage sensor 242 can be used. This isbecause these measured voltages can be regarded as identical dependingon the connection state of the shutoff device 230 and other relays (notillustrated).

While the internal combustion engine 210 is operating, the timing formaking the foregoing determination based on the current sensor 391 orthe voltage sensor 392 may be limited to the timing when the number ofrotations of the internal combustion engine 210 is equal to or greaterthan a predetermined number of rotations. That is, when the powergenerator 300 is normal, the determination may be made only at a timingwhen the measurement value from the voltage sensor 392 or the likebecomes large to some degree within a predetermined range.

Among the determinations listed above, the determination based on thecurrent value, the determination based on the regulator voltage (thevoltage value measured by the voltage sensor 382), and the determinationbased on the rotor voltage (the voltage value measured by the voltagesensor 364) may be made only at a timing when the system voltage becomeshigher than a predetermined value or a timing when the PCU 202 issues nopower generation instruction. This is because, when the system voltageis low to some degree, the current supplied to the rotor coil 321 may beintentionally increased even if no abnormality has occurred.

Among the determinations listed above, the determination based on thestator voltage value (the voltage value measured by the voltage sensor392) may be made only at a timing when the PCU 202 issues no powergeneration instruction.

In step S02, in addition to the determination on whether any abnormalityhas occurred in the power generator 300 as described above, it isdetermined whether there is a high risk of an abnormality occurring inthe power generator 300 (specifically, the underpower generation state)in a short time. The determination is made based on, out of the powergenerator information acquired by the information acquisition unit 110,the duration of use of the power generator 300. When the duration of theuse is longer than a predetermined value, it is determined that there isa high possibility of the power generator 300 entering the underpowergeneration state.

The duration of use of the power generator 300 may be determined basedon the time elapsed from the installation of the power generator 300into the automatic drive vehicle 200 or may be determined based onvarious indexes substantially proportional to the duration of use of thepower generator 300, such as the number of times the internal combustionengine 210 was started after the installation of the power generator300, the integrated value of the numbers of rotations of the internalcombustion engine 210, the running distance of the automatic drivevehicle 200, and the integrated value of the amounts of power generationby the power generator 300.

The result of the determination in step S02 is stored in the storageunit 150 of the control device 100. After step S02, it is determined instep S03 whether the automatic driving switch 290 is in the ON position.When the automatic driving switch 290 is in the ON position, the processproceeds to step S04.

In step S04, the result of the determination in step S02 is read fromthe storage unit 150. After that, it is determined whether the result ofthe determination in step S02 indicates that the power generator 300 isoperating normally (that is, the power generator 300 is not in theunderpower generation state or the overpower generation state). When itis determined that the power generator 300 is normal, the processproceeds to step S05.

In step S05, it is determined whether the result of the determination instep S02 indicates that (the power generator 300 is normal but) there isa high possibility of the power generator 300 entering the underpowergeneration state. When it is not determined that there is a highpossibility of the power generator 300 entering the underpowergeneration state, the process proceeds to step S06. In step S06, thedetermination unit 170 decides to switch to the first state. Accordingto the determination, the operation control unit 130 performs switchingto the first state. Specifically, the operation control unit 130switches to the state in which the automatic drive vehicle 200 executesautomatic driving without constraints. When the automatic drive vehicle200 has executed no automatic driving so far, the automatic drivevehicle 200 starts automatic driving from this point in time. When thepower generator 300 has been already in the first state at the time ofshift to step S06, this state is maintained.

The processing in step S02 may be performed at a timing after step S03and immediately before step S04.

When it is determined in step S05 that there is a high possibility ofthe power generator 300 entering the underpower generation state, theprocess proceeds to step S08. In step S08, the determination unit 170decides to switch to the second state. According to the determination,the operation control unit 130 performs switching to the second state.Specifically, the operation control unit 130 performs switching to thestate in which automatic driving of the automatic drive vehicle 200 ispartially or entirely restricted. When the power generator 300 has beenalready in the second state at the time of shifting to step S08, thisstate is maintained.

When it is not determined in step S04 that the power generator 300 isnormal, the process proceeds to step S07. In step S07, it is determinedwhether the result of the determination in step S02 indicates theunderpower generation state. When it is determined that the powergenerator 300 is in the underpower generation state, the processproceeds to step S08. In step S08, the determination unit 170 decides toswitch to the second state as described above, and then the switching tothe second state takes place.

When it is not determined in step S07 that the power generator 300 is inthe underpower generation state, the process proceeds to step S09.Shifting to step S09 means that some abnormality has occurred in thepower generator 300 and the abnormality is not underpower generation. Inthis case, it is presumed that the power generator 300 is in theoverpower generation state. Accordingly, in step S09, as a measureagainst overpower generation, the shutoff control unit 140 performs acontrol to switch the shutoff device 230 to the open state. Accordingly,the path to which power from the power generator 300 is output isopened, thereby to prevent application of a high voltage from the powergenerator 300 to the battery 240 and the auxiliary devices.

Upon completion of step S09, the process proceeds to step S08. In stepS08, the determination unit 170 decides to switch to the second state asdescribed above, and then the switching to the second state takes place.

In step S03, when the automatic driving switch 290 is in the OFF state,the process proceeds to step S10. In step S10, the determination unit170 decides to stop automatic driving. According to the determination,the operation control unit 130 performs a process of stopping automaticdriving. When automatic driving has been already unexecuted at the timeof proceeding to step S10, this state is maintained.

As described above, in the control device 100 according to the presentembodiment, when the power generator information acquired by theinformation acquisition unit 110 indicates the underpower generationstate in which power generation by the power generator 300 isinsufficient (an affirmative determination is made in step S07) or whenthere is a high possibility of the power generator 300 entering theunderpower generation state (an affirmative determination is made instep S05), the determination unit 170 decides to perform switching tothe second state by the operation control unit 130. Even when the powergeneration by the power generator 300 is insufficient, the shifting tothe state in which automatic driving is partially or entirely restrictedmakes it possible to continue automatic driving within the range ofconsumable power.

In the present embodiment, the power generator 300 is configured as analternator having the rotor coil 321 and the stator coil 311. The powergenerator information acquired by the information acquisition unit 110includes the current value in the rotor coil 321, the voltage value inthe rotor coil 321, the current value in the stator coil 311, and thevoltage value in the stator coil 311. Based on the power generatorinformation, the determination unit 170 decides whether the powergenerator 300 is in the underpower generation state (step S02).Comparing the current values and the voltage values in the individualcomponents of the power generator 300 makes it possible to detect anabnormality in the power generator 300 in a precise manner.

The power generator information acquired by the information acquisitionunit 110 includes a use history of the power generator 300. Based on thepower generator information, the determination unit determines whetherthere is a high possibility of the power generator 300 entering theunderpower generation state (step S05). This enables switching to thesecond state prior to the occurrence of an abnormality in the powergenerator 300. Accordingly, it is possible to prevent a situation inwhich the power generator 300 becomes defective during execution ofautomatic driving.

When the power generator information acquired by the informationacquisition unit 110 indicates the overpower generation state in whichthat power generation by the power generator 300 is excessive (anegative determination is made in step S07), the determination unit 170decides to perform switching to the second state by the operationcontrol unit 130. Even when power generation by the power generator 300is excessive, the shifting to the state in which automatic driving ispartially or entirely restricted makes it possible to continue automaticdriving within an executable range or prohibit or stop automaticdriving.

In the present embodiment, even if no power generator informationclearly indicating overpower generation is acquired, when the powergenerator 300 is not normally operating but is not in the underpowergeneration state, this situation is handled on the assumption that thepower generator 300 is in the overpower generation state. Accordingly,it is possible to prevent a situation in which no overpower generationcan be detected but automatic driving is continuously executed.

In another mode, it may be determined to switch to the second state whenthe power generator information indicating overpower generation isacquired. That is, it may be determined to switch to the second statewhen it is determined in step S02 that the power generator 300 is in theoverpower generation state by the method described above based on atleast one of the current value in the rotor coil 321, the voltage valuein the rotor coil 321, the current value in the stator coil 311, and thevoltage value in the stator coil 311 in the power generator information.In addition, it may be determined that the power generator 300 is in theoverpower generation state and it may be determined to switch to thesecond state when the temperature of the battery 240 (that is, thetemperature of the storage battery to which power from the powergenerator 300 is supplied) included in the power generator informationexceeds a predetermined value.

In the event of overpower generation, when the determination unit 170decides to perform switching to the second state by the operationcontrol unit 130, the shutoff control unit 140 controls the operationsof the shutoff device 230 to open the path to which power from the powergenerator 300 is output. Accordingly, it is possible to prevent asituation in which a high voltage from the power generator 300 isapplied to the battery 240 and the auxiliary devices that thus becomefailed.

After the switching to the second state, when the power generator 300returns to normal operation due to replacement by a new one, forexample, a process of canceling the restriction of automatic driving isperformed. This process will be specifically described with reference toFIG. 4 . The series of steps illustrated in FIG. 4 are repeatedlyexecuted by the control device 100 after each lapse of a specificperiod.

In first step S22, it is determined whether it was determined in stepS02 illustrated in FIG. 2 that there was a high possibility that thepower generator 300 (then normally operating) would enter the underpowergeneration state. When it was determined that there was a highpossibility of the power generator 300 entering in the underpowergeneration state, the process proceed to step S23.

In step S23, it is determined whether a signal for canceling therestriction of automatic driving has been transmitted from the externaldevice 400 to the communication unit 160. This signal can be said to bea signal indicating that the power generator 300 is normal. When thesignal for canceling the restriction of automatic driving has beentransmitted, the process proceeds to step S24. In step S24, a process ofcanceling the restriction of automatic driving is performed.

In this case, for example, the result of the determination stored in thestorage unit 150 (the result of the determination made in step S02) isrewritten to store the result that the power generator 300 is normal. Inother words, the result of the determination that there is a highpossibility of the power generator 300 entering in the underpowergeneration state is erased. In addition, the various kinds ofinformation indicating the indexes substantially proportional to theduration of use of the power generator 300 such as the integrated valueof the numbers of rotations of the internal combustion engine 210 andthe running distance of the automatic drive vehicle 200 is reset.

After step S24, when the automatic driving switch 290 is turned on, theswitching to the first state takes place. Alternatively, in step S24,the switching to the first state may take place immediately. The samething can be said to steps S28 and S32 described later.

In step S23, when the signal for canceling the restriction of automaticdriving has not been transmitted from the external device 400 to thecommunication unit 160, the series of steps illustrated in FIG. 4 areterminated without performing any processing. The automatic drivevehicle 200 is continuously kept in the second state.

As described above, in the present embodiment, the determination resultthat there is a high possibility of the power generator 300 entering theunderpower generation state is changed and the restriction of automaticdriving based on the change of the determination result is canceledbased on a signal transmitted from the external device 400. This isbecause, since there is a high possibility of the power generator 300entering the underpower generation state but the power generator 300 isnormally operating now, it is difficult for the control device 100 todetermine by itself that the possibility of entering the underpowergeneration state has become low due to the replacement of powergenerators later.

However, providing a mechanism to detect a specific ID of the powergenerator 300, for example, allows the control device 100 to determineby itself that the state in which “there is a high possibility of thepower generator 300 entering the underpower generation state” has beeneliminated due to the replacement of the power generator 300. Forexample, providing a reader to read a two-dimensional barcode on thepower generator 300 allows the control device 100 to detect that thepower generator 300 has been replaced with a new one based on theinformation from the two-dimensional barcode and cancel the restrictionof automatic driving according to the detection. In addition, thecontrol device 100 may determine whether the newly installed powergenerator 300 is a normal one and cancel the restriction of automaticdriving only when the power generator 300 is a normal one.

When it is not determined in step S22 that it was determined that therewas a high possibility of the power generator 300 entering theunderpower generation state, the process proceeds to step S25. In stepS25, it is determined whether it was determined in step S02 illustratedin FIG. 2 that the power generator 300 was in the underpower generationstate. When it was determined that the power generator 300 was in theunderpower generation state, the process proceeds to step S26.

In step S26, similarly to step S01 illustrated in FIG. 3 , theinformation acquisition unit 110 acquires the power generatorinformation. In step S27 after step S26, similarly to step S02illustrated in FIG. 3 , it is determined whether there has occurred anabnormality in the power generator 300. When it is determined that thepower generator 300 is normal, the process proceeds to step S28. In stepS28, similarly to step S24, a process of canceling the restriction ofautomatic driving is performed.

When it is not determined in step S27 that the power generator 300 isnormal, the series of steps illustrated in FIG. 4 are terminated.Accordingly, the automatic drive vehicle 200 is continuously kept in thesecond state.

When it was determined that the power generator 300 was not in theunderpower generation state in step S25, the process proceeds to stepS29. In step S29, similarly to step S01 illustrated in FIG. 3 , theinformation acquisition unit 110 acquires the power generatorinformation. In step S30 After step S29, similarly to step S02illustrated in FIG. 3 , it is determined whether there has occurred anabnormality in the power generator 300. When it is determined that thepower generator 300 is normal, the process proceeds to step S31.

Proceeding to step S31 means that the overpower generation in the powergenerator 300 has been eliminated. In step S31, a process of switchingthe shutoff device 230 brought into the open state in step S09illustrated in FIG. 3 to the closed state. In step S32 After step S31,similarly to step S24, a process of canceling the restriction ofautomatic driving is performed. When it is determined in step S30 thatthere has occurred an abnormality in the power generator 300, the seriesof steps illustrated in FIG. 4 are terminated without performing anyprocessing.

As described above, in the control device 100 according to the presentembodiment, after the switching to the second state, when theinformation acquisition unit 110 acquires the power generatorinformation indicating that the power generator is normal (anaffirmative determination is made in step S27 or step S30), therestriction of automatic driving is canceled and the operation controlunit 130 performs the switching to the first state.

Similarly, after the switching to the second state, when the externaldevice 400 supplies a signal indicating that the power generator 300 isnormal (a negative determination is made in step S23), the restrictionof automatic driving is canceled and the operation control unit 130performs the switching to the first state. According to thisconfiguration, it is possible to cancel the restriction of automaticdriving at an appropriate timing.

In the example illustrated in FIG. 4 , the restriction is canceled basedon the signal from the external device 400 only when it was determinedin step S02 illustrated in FIG. 2 that “there is a high possibility ofentering the underpower generation state”. In another mode, a process asin a modification example illustrated in FIG. 5 may be performed.

In the first step S41 of the process illustrated in FIG. 5 , similarlyto step S23 illustrated in FIG. 4 , it is determined whether a signalfor canceling the restriction of automatic driving has been transmittedfrom the external device 400 to the communication unit 160. When it isnot determined that a signal for canceling the restriction of automaticdriving has been transmitted from the external device 400 to thecommunication unit 160, the series of steps illustrated in FIG. 5 areterminated without performing any processing. The automatic drivevehicle 200 is continuously kept in the second state.

When it is determined in step S41 that a signal for canceling therestriction of automatic driving has been transmitted from the externaldevice 400 to the communication unit 160, the process proceeds to stepS42. In step S42, similarly to step S24 illustrated in FIG. 4 , aprocess of canceling the restriction of automatic driving is performed.At this time, when the shutoff device 230 is in the open state, theshutoff control unit 140 performs a control of switching the shutoffdevice 230 to the closed state in step S42.

In the modification example illustrated in FIG. 5 , whatever abnormalityhas occurred in the power generator 300, the restriction is canceledbased on the signal from the external device 400. That is, the controldevice 100 does not determine whether the power generator 300 has becomenormal but cancels the restriction only based on the signal from theexternal device 400. Even in this mode, the same advantageous effects asdescribed above with reference to FIG. 4 can be produced.

Another modification example illustrated in FIG. 4 will be describedwith reference to FIG. 6 . The series of steps illustrated in FIG. 6 areexecuted instead of step S29 and the subsequent steps illustrated inFIG. 4 when a negative determination is made in step S25 illustrated inFIG. 4 .

In first step S51, similarly to step S23 illustrated in FIG. 4 , it isdetermined whether a signal for canceling the restriction of automaticdriving has been transmitted from the external device 400 to thecommunication unit 160. When it is not determined that a signal forcanceling the restriction of automatic driving has been transmitted fromthe external device 400 to the communication unit 160, the series ofsteps illustrated in FIG. 6 are terminated without performing anyprocessing. The automatic drive vehicle 200 is continuously kept in thesecond state.

When it is determined in step S51 that a signal for canceling therestriction of automatic driving has been transmitted from the externaldevice 400 to the communication unit 160, the process proceeds to stepS52. In step S52, the shutoff control unit 140 performs a control ofswitching the shutoff device 230 to the closed state. In step S53 Afterstep S52, similarly to step S01 illustrated in FIG. 3 , the informationacquisition unit 110 acquires the power generator information. In stepS54 After step S53, similarly to step S02 illustrated in FIG. 3 , it isdetermined whether there has occurred an abnormality in the powergenerator 300. When it is determined that the power generator 300 isnormal, the process proceeds to step S55.

Proceeding to step S55 means that the overpower generation in the powergenerator 300 has been eliminated. In step S55, similarly to step S24illustrated in FIG. 4 , a process of canceling the restriction ofautomatic driving is performed. When it is determined in step S54 thatthere has occurred an abnormality in the power generator 300, the seriesof steps illustrated in FIG. 6 are terminated without performing anyprocessing.

As described above, in the modification example illustrated in FIG. 6 ,the external device 400 performs a process of switching the shutoffdevice 230 to the closed state but does not perform a process ofcanceling the restriction of automatic driving. The latter process isperformed by the control device 100. Even in this mode, the sameadvantageous effects as described above with reference to FIG. 4 can beproduced.

A second embodiment will be described with reference to FIG. 7 .Hereinafter, differences from the first embodiment will be mainlydescribed and descriptions of the points in common with the firstembodiment will be omitted as appropriate.

The series of steps illustrated in FIG. 7 are executed instead of theseries of steps illustrated in FIG. 3 . In the series of stepsillustrated in FIG. 7 , step S08 in the series of steps illustrated inFIG. 3 is replaced by steps S15, S16, and S17. Among the stepsillustrated in FIG. 7 , the same steps as those illustrated in FIG. 3are given the same reference numerals (such as “S01”) as illustrated inFIG. 3 .

When an affirmative determination is made in step S05, or when anaffirmative determination is made in step S07, or after step S09 isperformed, the process proceeds to step S15. That is, when there arisesthe need to switch to the second state, the process proceeds to stepS15.

In step S15, it is determined whether an automatic drive vehicle 200 isrunning on a motorway and whether the automatic drive vehicle 200 isgoing to run a motorway. This determination is made based on a signalfrom a navigation system 280.

When the automatic drive vehicle 200 is not running on a motorway or isnot going to run on a motorway, the process proceeds to step S17. Instep S17, similarly to step S08 illustrated in S17, a determination unit170 decides to switch to a second state. According to the determination,an operation control unit 130 performs switching to the second state.

When it is determined in step S15 that the automatic drive vehicle 200is running on a motorway or is going to run on a motorway, the processproceeds to step S16. In step S16, the determination unit 170 decides toswitch to a second state. The operation control unit 130 performsswitching to the second state. The second state switched in step S16 isdifferent from the second state switched in step S17. Therefore, thesecond state in step S16 will be described as “second state A” and thesecond state in step S17 will be described as “second state B”.

When the process proceeds to step S16 (switches to the second state A),automatic driving is restricted greatly as compared to the case wherethe process proceeds to step S17 (switches to the second state B). Forexample, only automatic steering is restricted in the second state B instep S17, whereas both automatic steering and automatic driving arerestricted in the second state Ain step S16.

When the power generator 300 becomes defective while the automatic drivevehicle 200 is running on a motorway, it is difficult to evacuateautomatically and safely the automatic drive vehicle 200 only by powersupply from the battery 240. On the other hand, when the automatic drivevehicle 200 is running on a general road, even when the power generator300 becomes defective, there is a high possibility that the automaticdrive vehicle 200 can be evacuated automatically and safely by powersupply from the battery 240. Accordingly, in the present embodiment,when the automatic drive vehicle 200 is running on a motorway, theautomatic driving in the second state is greatly restricted as comparedto the case where the automatic drive vehicle 200 is not running on amotorway. Accordingly, it is possible to prevent a situation in whichthe power generator 300 becomes defective during running on a motorwayand power supply is lost during automatic driving.

In an aspect, when it is determined in step S15 that the automatic drivevehicle 200 is going to run on a motorway, in addition to the switchingto the second state, the guided route may be changed so that theautomatic drive vehicle 200 will not run on a motorway.

A third embodiment will be described with reference to FIG. 8 .Hereinafter, differences from the first embodiment will be mainlydescribed, and descriptions of points in common with the firstembodiment will be omitted as appropriate.

The series of steps illustrated in FIG. 8 are repeatedly executed by acontrol device 100 after each lapse of a predetermined period in thestate in which an internal combustion engine 210 is automaticallystopped by an internal combustion engine control unit 120, that is, inan idle stop state. In the present embodiment, the series of stepsillustrated in FIG. 8 are executed in parallel to the other stepsillustrated in FIGS. 3 and 4 .

In first step S61, the internal combustion engine control unit 120determines whether a first request from a vehicle ECU 201 has beenreceived by a communication unit 160. As described above, the firstrequest is a control signal transmitted from the vehicle ECU 201 to thecontrol device 100 to start the internal combustion engine 210 when thedriving force for running an automatic drive vehicle 200 becomesnecessary.

When the first request has been received, the process proceeds to stepS62. In step S62, the internal combustion engine control unit 120executes a process of starting the internal combustion engine 210 toreturn from the idle stop state. After that, the control device 100terminates the series of steps illustrated in FIG. 8 .

When it is not determined in step S61 that the first request has beenreceived, the process proceeds to step S63. In step S63, it isdetermined whether a second request from the vehicle ECU 201 has beenreceived by the communication unit 160. As described above, the secondrequest is a control signal transmitted from the vehicle ECU 201 to thecontrol device 100 to start the internal combustion engine 210 whenpower generation by a power generator 300 becomes necessary.

When the second request has not been received, the series of stepsillustrated in FIG. 8 is terminated without starting the internalcombustion engine 210. When the second request has been received, theprocess proceeds to step S64. In step S64, similarly to step S01illustrated in FIG. 3 , the information acquisition unit 110 acquiresthe power generator information. In step S65 After step S64, similarlyto step S02 illustrated in FIG. 3 , it is determined whether anabnormality has occurred in the power generator 300. When it isdetermined that the power generator 300 is normal, the process proceedsto step S62. After that, a process of starting the internal combustionengine 210 is performed to return from the idle stop state.

When it is determined in step S65 that an abnormality has occurred inthe power generator 300, the control device 100 terminates the series ofsteps illustrated in FIG. 8 without starting the internal combustionengine 210. As described above, in the present embodiment, when thepower generator information acquired by the information acquisition unit110 indicates that power generation is not been performed normally bythe power generator 300, the internal combustion engine control unit 120does not return from the idle stop state even in the event of receipt ofthe second request. In addition, the vehicle ECU 201 may be configurednot to output the second request when recognizing that the powergenerator 300 is in a failed state.

Accordingly, it is possible to avoid a situation in which the internalcombustion engine 210 is unnecessarily started when the power generationis not being performed normally by the power generator 300. When thegeneration of driving force is intended, that is, when the first requesthas been received, the internal combustion engine 210 is started.

The embodiments have been described so far with reference to specificexamples. However, the present disclosure is not limited to thesespecific examples. These specific examples to which design changes areadded as appropriate are also in the scope of the present disclosure asfar as they include features of the present disclosure. The elementsincluded in the specific examples, the arrangements, conditions, andshapes of the elements described above are not limited to theexemplified ones but can be changed as appropriate. The elementsincluded in the specific examples described above can be changed incombination as appropriate as far as the change causes no technicalcontradictions.

What is claimed is:
 1. A method of controlling an automatic drivevehicle that includes: at least one computer system that is configuredto control certain operational activities of the automatic drivevehicle; a battery that supplies power to operate the at least onecomputer system; and a temperature sensor configured to measure atemperature of the battery, the method comprising the steps of: the atleast one computer system acquiring the temperature of the batterymeasured by the temperature sensor; and the at least one computer systemdetermining whether (i) all of the certain operational activities areconducted in an automatic driving mode in a first control state or (ii)one or more of the certain operational activities are conducted in theautomatic driving state without restriction while at least another ofthe certain operational activities is conducted with restriction in theautomatic driving mode or is not conducted in the automatic driving modein a second control state based on the temperature of the battery. 2.The method of controlling the automatic drive vehicle according to claim1, wherein the at least one computer system, in the second controlstate, prevents the loss of power during the automatic driving mode suchthat the automatic drive vehicle is automatically and safely operated bythe power from the battery.
 3. The method of controlling the automaticdrive vehicle according to claim 2, wherein the certain operationalactivities include a running speed of the automatic drive vehicle. 4.The method of controlling the automatic drive vehicle according to claim3, wherein an inter-terminal voltage of the battery is obtained by theat least one computer system, and the at least one computer systemdetermines, in the second control state, which of the certainoperational activities should be restricted when the inter-terminalvoltage becomes lower than a predetermined value.
 5. The method ofcontrolling the automatic drive vehicle according to claim 1, whereinthe at least one computer system switches from the first control stateto the second control state when the temperature of the battery exceedsa predetermined value.
 6. The method of controlling the automatic drivevehicle according to claim 5, wherein when the battery is replaced, apart of information stored in a storage unit of the automatic drivevehicle is rewritten.
 7. An automatic drive vehicle comprising: at leastone computer system that is configured to control certain operationalactivities of the automatic drive vehicle; a battery configured tosupply power to operate the at least one computer system; and atemperature sensor configured to measure a temperature of the battery,wherein the at least one computer system is configured to: acquire thetemperature of the battery measured by the temperature sensor; anddetermine whether (i) all of the certain operational activities areconducted in an automatic driving mode in a first control state or (ii)one or more of the certain operational activities are conducted in theautomatic driving mode without restriction while at least another of thecertain operational activities is conducted with restriction in theautomatic driving mode or is not conducted in the automatic driving modein a second control state based on the temperature of the battery. 8.The automatic drive vehicle according to claim 7, wherein the at leastone computer system is configured to, in the second control state,prevent the loss of power during the automatic driving mode such thatthe automatic drive vehicle is safely operated by the power from thebattery.
 9. The automatic drive vehicle according to claim 8, whereinthe certain operational activities include a running speed of theautomatic drive vehicle.
 10. The automatic drive vehicle according toclaim 9, wherein the at least one computer system is configured to:obtain an inter-terminal voltage of the battery; determine, in thesecond control state, which of the certain operational activities shouldbe restricted when the inter-terminal voltage becomes lower than apredetermined value.
 11. The automatic drive vehicle according to claim9, wherein the at least one computer system switches from the firstcontrol state to the second control state when the temperature of thebattery exceeds a predetermined value.
 12. The automatic drive vehicleaccording to claim 11, wherein the automatic drive vehicle is configuredsuch that when the battery is replaced, a part of information stored ina storage unit of the automatic drive vehicle is rewritten.
 13. Themethod of controlling the automatic drive vehicle of claim 1, whereinthe certain operational activities include vehicle steering, vehiclebraking and vehicle driving force.
 14. The method of controlling theautomatic drive vehicle of claim 1, wherein the certain operationalactivities consist of vehicle steering, vehicle braking and vehicledriving force.
 15. The automatic drive vehicle according to claim 7,wherein the certain operational activities include vehicle steering,vehicle braking and vehicle driving force.
 16. The automatic drivevehicle of claim 7, wherein the certain operational activities consistof vehicle steering, vehicle braking and vehicle driving force.